The religious urge in man is not a mere passing phase in the history of his spiritual development, but the ultimate source of all his ethical thought and all his concepts of morality; not the outcome of primitive credulity which a more "enlightened" age could outgrow, but the only answer to a real, basic need of man at all times and in all environments. In another word, it is an instinct.
Muhammad Asad (1961). “The Principles of State and Government in Islam”, p.10, Univ of California Press